This invention relates to a fitting for mounting to the ends of smooth wall tubes, particularly tubes of copper or aluminum having on the end thereof a bead or a flange fitting brazed thereto.
The fitting of the present invention is generally related to those types of fittings disclosed in the U.S. Pat. Nos. 3,738,688; 3,779,587; and 3,868,132.
The fittings disclosed in the above-mentioned United States patents are mounted to the end of a smooth wall tube by, generally, compressing a tubular plug against the outer diameter of the tube upon translation of a ram element within the housing thereof. Such fittings provide a good seal and holding action so that fluids passing through the smooth wall tube may be sealed by the fitting, or may be conveyed out of the fitting into auxiliary tubing mounted thereto.
The fittings disclosed in the above-mentioned copending application Ser. No. 901,609, are particularly designed for application on short protrusion or expanded refrigeration and air conditioning tube ends existing on all industrial components, such as, for example, condensers, evaporators, compressors, header assemblies and the like. In many cases, the tubing is thin-walled, and fittings of the type disclosed in the above-identified United States patents can distort the tube ends when fitted thereto.
Accordingly, this copending application provides a fitting that not only grips on the outside diameter, but also seals on the inside diameter. The counter forces of ID sealing and OD gripping at the same point eliminate the possibility of tube distortion especially on minimum wall tubing even at elevated pressures.
In many applications where a rubber tube or hose is to be attached to a connection such as the end of a smooth wall tube, the tube has a bead provided on its end, or a flange fitting is brazed to its end. The rubber tube or hose is slipped over the bead onto the tube, or onto the flange fitting, and then is secured thereon with a clamp. The bead in combinaton with the clamp provides greater securement on the rubber tube or hose with the connection. The fitting of the present invention is particularly applicable for use with smooth wall tubes of this type, to both grip and seal the tube on its inside diameter.
Accordingly, it is an object of the present invention to provide an improved fitting for mounting to the ends of smooth wall tubes. More particularly, it is an object to provide such a fitting which is designed for application on tubes having beads or flange fittings on the ends thereof, to grip and to seal the inside diameter of the tube.